Clarifying the nomenclature of Strychnosbredemeyeri and Lasiostoma (Loganiaceae).

Strychnos (Loganiaceae, Gentianales) is a large and pantropical genus of woody plants, ethnobotanically important as a source of many toxic alkaloids, including strychnine. Unfortunately, the status of numerous names at various ranks of Strychnos remains unresolved, including that of many specific or infraspecific taxa in the Neotropics. In this study, we address Strychnosbredemeyeri (basionym Lasiostomabredemeyeri), a species described in 1827 based on type material collected in Venezuela during the poorly documented Austrian Märter expedition (1783-1788). Strychnosbredemeyeri is an unarmed liana with solitary tendrils and axillary inflorescences that occurs in Neotropical rainforests and savannas in Brazil, Guyana, Trinidad and Tobago, and Venezuela. We clarify here the nomenclatural status of Lasiostoma Schreb., an illegitimate and superfluous genus currently in synonymy under Strychnos, and its former species Lasiostomabredemeyeri [= Strychnosbredemeyeri]. Also, we lectotypify S.pedunculata and S.trinitensis, both taxa currently synonyms of S.bredemeyeri.

Organellar-genome analyses from the lycophyte genus Isoetes L. show one of the highest frequencies of RNA editing in land plants.

RNA editing is a post-transcriptional process that challenges the central dogma of molecular biology by modifying RNA sequences, introducing nucleotide changes at specific sites, and generating functional diversity beyond the genomic code, especially when it concerns organellar transcripts. In plants, this phenomenon is widespread, but its extent varies significantly among species and organellar genomes. Among land plants, the heterosporous lycophytes (i.e., Isoetes and Selaginella) stand out for their exceptionally high numbers of RNA-editing sites, despite their morphological stasis and ancient lineage. In this study, we explore the complete set of organellar protein-coding genes in the aquatic plant group Isoetes, providing a detailed analysis of RNA editing in both the mitochondrial and plastid genomes. Our findings reveal a remarkable abundance of RNA editing, particularly in the mitochondrial genome, with thousands of editing sites identified. Interestingly, the majority of these edits result in non-silent substitutions, suggesting a role in fine-tuning protein structure and function. Furthermore, we observe a consistent trend of increased hydrophobicity in membrane-bound proteins, supporting the notion that RNA editing may confer a selective advantage by preserving gene functionality in Isoetes. The conservation of highly edited RNA sequences over millions of years underscores the evolutionary significance of RNA editing. Additionally, the study sheds light on the dynamic nature of RNA editing, with shared editing sites reflecting common ancestry whereas exclusive edits matching more recent radiation events within the genus. This work advances our understanding of the intricate interplay between RNA editing, adaptation, and evolution in land plants and highlights the unique genomic features of Isoetes, providing a foundation for further investigations into the functional consequences of RNA editing in this enigmatic plant lineage.

Areas of endemism of Pteridaceae (Polypodiopsida) in Brazil: a first approach.

Areas of endemism (AoE) comprise regions host to two or more endemic taxa, whose distributional limits are congruent and not random. These areas are important for two reasons: they comprise the smallest geographic units for biogeographic analyses and they are priority targets for conservation actions. Ferns are a monophyletic group that despite having a wide geographic distribution, concentrates great species richness and endemism in some regions (centres). The southern and southeastern regions of Brazil comprise one of these centres for the Neotropics. This study aims to verify the AoE of Pteridaceae in Brazil and examine whether the results obtained here are congruent with areas already delimited for other groups and whether there is spatial correspondence between the AoE and Conservation Units. To this end, a database was created with collection records of the 205 Pteridaceae species occurring in Brazil based on a review of herbaria. We analysed 23 815 records for 205 Pteridaceae species using Endemicity Analysis (NDM-VNDM), selecting the fill and assumed parameters, and 1°, 2° and 3° grid-cells. The consensus of 158 AoE, using different grid sizes, was calculated, and subsequently, generalized AoE were established. The Guiana Shield, southern Brazil, southeastern Brazil, and southeastern Bahia were considered generalized AoE. These areas correspond to those found for animals and angiosperms, and in previous studies with ferns. Furthermore, two areas, Acre and Mato Grosso do Sul, were recovered only on grids with 2° and 3°. It will be essential to conduct more research to confirm the persistence of both AoE (Acre and Mato Grosso do Sul), especially after expanding sampling. Most endemic species distribution points occur outside protected areas, demonstrating an alarming situation regarding the conservation of these taxa. In addition, fern distribution data could (and should) be used in conservation practices, programmes and policies, given that they are good ecological indicators and that the distribution of ferns may not reflect that of angiosperms and animals.

Lycophytes and ferns of an Amazonian-Cerrado ecotone in Maranhão State, Northeastern Brazil: identification key and annotated list of taxa / Licófitas e samambaias de um ecótono Amazonia-Cerrado no estado do Maranhão, Nordeste do Brasil: chave de identificação de lista anotada dos táxons

Abstract We present a key to identify and an annotated list of lycophytes and ferns of the Immediate Geographical Region of São Luís, Maranhão State, which has ecotonal characteristics of Amazonian Forest, Cerrado, and Coastal Vegetation. Specimens were collected monthly between April 2020 and September 2022 in the 13 municipalities of this region. A total of 64 species were identified, including 61 species of ferns, in 18 families and 38 genera, and three species of lycophytes, in two genera and one family. The most representative families were Pteridaceae (18 species) and Polypodiaceae (nine species). The most recorded substrate of occurrence was terrestrial with 35 species (54.6%), followed by epiphytic with 15 species (23.4%), aquatic with four species (6.2%), rupicolous with three species (4.6%), and hemiepiphytic with two species (3.1%). Five species (7.8%) had more than one life form. This study expands the knowledge about the geographic distribution of fern and lycophyte species in the central region of Northern Maranhão, in Northeastern Brazil, which until now had several sampling gaps. Maranhão has a diversity that is still poorly reported and known compared to other states in South and Southeast Brazil. Therefore, floristic surveys are essential to increase what is known about the flora, especially in areas under anthropic pressure and places with few collections, such as the ecotonal areas in Maranhão.

Resumo Apresentamos uma chave para a identificação e uma lista com detalhes das licófitas e samambaias da Região Geográfica Imediata de São Luís, Estado do Maranhão, que possui características ecotonais da Floresta Amazônica, Cerrado e Vegetação Litorânea. Os dados foram coletados mensalmente entre abril de 2020 e setembro de 2022 nos 13 municípios dessa região. Foram identificadas 64 espécies, incluindo 61 espécies de samambaias, em 18 famílias e 38 gêneros, e três espécies de licófitas, em dois gêneros e uma família. As famílias mais representativas foram Pteridaceae (18 espécies) e Polypodiaceae (nove espécies). O substrato de ocorrência mais registrado foi o terrestre com 35 espécies (54,6%), seguido do epifítico com 15 espécies (23,4%), aquático com quatro espécies (6,2%), rupícola com três espécies (4,6%) e hemiepifítico com duas espécies (3,1%). Cinco espécies (7,8%) apresentaram mais de uma forma de vida. Este estudo amplia o conhecimento sobre a distribuição geográfica de espécies de samambaias e licófitas na região central do norte do Maranhão, no Nordeste do Brasil, que até então possuía várias lacunas de amostragem. O Maranhão possui uma diversidade ainda pouco relatada e conhecida em comparação com outros estados das regiões Sul e Sudeste do Brasil. Portanto, levantamentos florísticos são essenciais para aumentar o conhecimento sobre a flora, principalmente em áreas sob pressão antrópica e locais com poucas coletas, como as áreas ecotonais do Maranhão.

Plastome-based phylogenomics elucidate relationships in rare Isoëtes species groups from the Neotropics.

The genus Isoëtes is globally distributed. Within the Neotropics, Isoëtes occurs in various habitats and ecosystems, making it an interesting case study to address phylogenetic and biogeographic questions. We sequenced and assembled plastomes and ribosomal DNA (rDNA) sequences to reconstruct phylogenetic relationships in Isoëtes from tropical regions in the Neotropics. The ploidy level of nine taxa was established to address the potential source of phylogenetic incongruence in the genus. Node ages were estimated using MCMCTree. The ancestral range estimates were conducted in BioGeoBEARS. Plastome-based phylogenies were congruent throughout distinct matrices and partition schemes, exhibiting high support for almost all nodes. Whereas, we found incongruences between the rDNA and plastome datasets. Chromosome counts identified three diploids, five tetraploids and one likely hexaploid among Neotropical species. Plastome-based node age estimates showed that the radiation of the crown Isoëtes group occurred at 20 Ma, with the diversification of the tropical American (TAA) clade taking place in the Pleistocene at 1.7 Ma. Ancestral range estimates showed that the ancestor of the TAA clade may have evolved first in the dry diagonal area in South America before reaching more humid regions. In addition, the colonization of the Brazilian semiarid region occurred three times, while the occupation of the Cerrado and Amazon regions occurred twice and once, respectively. Our study showed a large unobserved diversity within the genus in warm-dry regions in the Neotropics. Plastomes provided sufficient genomic information to establish a robust phylogenetic framework to answer evolutionary questions in Isoëtes from the Neotropics.

Class I KNOX Is Related to Determinacy during the Leaf Development of the Fern Mickelia scandens (Dryopteridaceae).

Unlike seed plants, ferns leaves are considered to be structures with delayed determinacy, with a leaf apical meristem similar to the shoot apical meristems. To better understand the meristematic organization during leaf development and determinacy control, we analyzed the cell divisions and expression of Class I KNOX genes in Mickelia scandens, a fern that produces larger leaves with more pinnae in its climbing form than in its terrestrial form. We performed anatomical, in situ hybridization, and qRT-PCR experiments with histone H4 (cell division marker) and Class I KNOX genes. We found that Class I KNOX genes are expressed in shoot apical meristems, leaf apical meristems, and pinnae primordia. During early development, cell divisions occur in the most distal regions of the analyzed structures, including pinnae, and are not restricted to apical cells. Fern leaves and pinnae bear apical meristems that may partially act as indeterminate shoots, supporting the hypothesis of homology between shoots and leaves. Class I KNOX expression is correlated with indeterminacy in the apex and leaf of ferns, suggesting a conserved function for these genes in euphyllophytes with compound leaves.

A list of land plants of Parque Nacional do Caparaó, Brazil, highlights the presence of sampling gaps within this protected area.

BACKGROUND: Brazilian protected areas are essential for plant conservation in the Atlantic Forest domain, one of the 36 global biodiversity hotspots. A major challenge for improving conservation actions is to know the plant richness, protected by these areas. Online databases offer an accessible way to build plant species lists and to provide relevant information about biodiversity. A list of land plants of "Parque Nacional do Caparaó" (PNC) was previously built using online databases and published on the website "Catálogo de Plantas das Unidades de Conservação do Brasil." Here, we provide and discuss additional information about plant species richness, endemism and conservation in the PNC that could not be included in the List. We documented 1,791 species of land plants as occurring in PNC, of which 63 are cited as threatened (CR, EN or VU) by the Brazilian National Red List, seven as data deficient (DD) and five as priorities for conservation. Fifity-one species were possible new ocurrences for ES and MG states. NEW INFORMATION: "Parque Nacional do Caparaó" houses 8% of the land plant species endemic to the Brazilian Atlantic Forest, including 6% of its angiosperms, 31% of its lycophytes and ferns and 14% of its avascular plants. Twelve percent of the threatened species listed for the State of Espírito Santo and 7% listed for the State of Minas Gerais are also protected by PNC. Surprisingly, 79% of the collections analysed here were carried out in Minas Gerais, which represents just 21% of the total extension of the Park. The compiled data uncover a huge botanical collection gap in this federally-protected area.

Adiantum (Pteridaceae) in Brazil: Key to the species and illustrations / Adiantum (Pteridaceae) no Brasil: chave para as espécies e ilustrações

Abstract: Adiantum is a Pantropical genus of ferns, monophyletic, and has about 225 species. It can be recognized by the indusia with veins, bearing sporangia directly on the underside of its reflexed tissue. About 110 species occur in the Neotropical region and 65 of them are reported to Brazil. Among them, 64 are native species and occur mainly in the Amazon Rainforest, Caatinga, Central Brazilian Savanna, and in the Brazilian Atlantic Rainforest. Among the species that occur in Brazil, 16 are endemic and they represent 25% of the total. This paper presents a key to identify the 63 native species of Adiantum in Brazil, excluding the hybrid one. Illustrations of some morphological features, as well as of all species are also presented to help in the process of identification.

Resumo: Adiantum é um gênero Pantropical de samambaias, monofilético e com cerca de 225 espécies. Pode ser reconhecido pelos indúsios com nervuras e esporângios formados diretamente sobre a face inferior do seu tecido reflexo. Aproximadamente 110 espécies ocorrem na região Neotropical e 65 delas são registradas para o Brasil. Entre elas, 64 são espécies nativas e ocorrem principalmente na Floresta Amazônica, Caatinga, nas vegetações abertas do Brasil Central e na Floresta Atlântica Brasileira. Entre a espécies que ocorrem no Brasil, 16 são endêmicas e elas representam 25% do total. Este trabalho apresenta uma chave para identificação das 63 espécies nativas de Adiantum no Brasil, excluindo o híbrido. Também são apresentadas ilustrações de alguns caracteres morfológicos, bem como de todas as espécies para ajudar no processo de identificação.

Jamesonia (Pteridaceae) in Brazil / Jamesonia (Pteridaceae) no Brasil

Abstract: Jamesonia is a genus of Neotropical ferns that comprises about 50 species, distributed from Mexico to Uruguay. In spite of this wide distribution, this group is more diverse in Andean páramos and subpáramos. Due to the recent changes in its circumscription, with the junction of Eriosorus and segregation of Tryonia, the objective of this work was to carry out the taxonomic study of Jamesonia for Brazil, in order to elaborate its monograph to the Flora of Brazil 2020. This study was based on morphological analyses of specimens deposited in 25 Brazilian herbaria, plus online images of types, field expeditions in the southern and southeastern regions of Brazil, revision of the literature, and scanning electronic microscopy of the spores. Seven species and two hybrids were recognized: J. biardii, J. brasiliensis, J. cheilanthoides, J. flexuosa, J. insignis, J. osteniana, J. rufescens, J. brasiliensis × J. cheilanthoides, and J. ×intermedia, respectively. A distinct specimen, from the border of Brazil (Amazonas) and Venezuela, was treated as Jamesonia sp., due to the presence of only one material. Identification key, descriptions and illustrations are provided for the species and hybrids, as well as, geographical distribution data, comments, list of selected material examined for each taxon, and a full list of all exsiccatae analyzed. We also present an identification key for the genera Jamesonia and Tryonia.

Resumo: Jamesonia é um gênero de samambaias Neotropical, que compreende cerca de 50 espécies, distribuídas do México ao Uruguai. Apesar dessa ampla distribuição, o grupo é mais diverso nos páramos e subpáramos andinos. Devido às recentes mudanças na sua circunscrição, com a junção de Eriosorus e a segregação de Tryonia, o objetivo desse trabalho foi realizar o estudo taxonômico de Jamesonia para o Brasil, a fim de elaborar sua monografia para a Flora do Brasil 2020. Esse estudo foi baseado na análise morfológica de espécimes depositados em 25 herbários nacionais, mais imagens dos tipos online, expedições de campo para as regiões sul e sudeste do Brasil, revisão de literatura, e microscopia eletrônica de varredura dos esporos. Sete espécies e dois híbridos foram reconhecidos: J. biardii, J. brasiliensis, J. cheilanthoides, J. flexuosa, J. insignis, J. osteniana, J. rufescens, J. brasiliensis × J. cheilanthoides e J. ×intermedia, respectivamente. Um espécime distinto, oriundo da fronteira do Brasil (Amazonas) com a Venezuela, foi tratado como Jamesonia sp., devido à presença de somente um material. Chaves de identificação, descrições e ilustrações foram apresentadas para as espécies e híbridos, bem como, dados de distribuição geográfica, comentários, lista de material selecionado examinado para cada táxon e uma lista contendo todas as exsicatas analisadas. Nós também apresentamos uma chave de identificação para os gêneros Jamesonia e Tryonia.

A free-access online key to identify Amazonian ferns.

There is urgent need for more data on species distributions in order to improve conservation planning. A crucial but challenging aspect of producing high-quality data is the correct identification of organisms. Traditional printed floras and dichotomous keys are difficult to use for someone not familiar with the technical jargon. In poorly known areas, such as Amazonia, they also become quickly outdated as new species are described or ranges extended. Recently, online tools have allowed developing dynamic, interactive, and accessible keys that make species identification possible for a broader public. In order to facilitate identifying plants collected in field inventories, we developed an internet-based free-access tool to identify Amazonian fern species. We focused on ferns, because they are easy to collect and their edaphic affinities are relatively well known, so they can be used as an indicator group for habitat mapping. Our key includes 302 terrestrial and aquatic entities mainly from lowland Amazonian forests. It is a free-access key, so the user can freely choose which morphological features to use and in which order to assess them. All taxa are richly illustrated, so specimens can be identified by a combination of character choices, visual comparison, and written descriptions. The identification tool was developed in Lucid 3.5 software and it is available at http://keyserver.lucidcentral.org:8080/sandbox/keys.jsp.

Fern and lycophyte flora of Acre state, Brazil / Flora de samambaias e licófitas do estado do Acre, Brasil

Abstract This paper provides keys, illustrations, short descriptions, and voucher specimen citations for the ferns and lycophytes of Acre, Brazil. We recognize a total of 212 species in 66 genera and 28 families. Of these, the lycophytes are represented by 14 species, 4 genera, and 2 families, and the ferns by 8 varieties, 1 subspecies, 198 species, 62 genera, and 26 families. The total represents an increase of 22 species and two varieties compared to a checklist published in 2009. The six most species-rich genera are Adiantum (21 spp.), Asplenium (14), Selaginella (12), Trichomanes (11), Lindsaea, and Microgramma (9 each). None of the species treated here are endemic to Acre. A new combination is made for Meniscium chrysodioides Fée var. goyazense.

Resumo Este trabalho fornece chaves, ilustrações, descrições curtas e citações de material examinado para as samambaias e licófitas do Acre, Brasil. Um total de 212 espécies, 66 gêneros e 28 famílias é reconhecido. Dentre estes, as licófitas constituem 14 espécies, 4 gêneros e 2 famílias e as samambaias 8 variedades, 1 subespécie, 198 espécies, 62 gêneros e 26 famílias. O total representa um aumento de 22 espécies e duas variedades comparado ao checklist publicado em 2009. Os seis gêneros mais ricos são Adiantum (21 spp.), Asplenium (14), Selaginella (12), Trichomanes (11), Lindsaea e Microgramma (9 cada). Nenhuma das espécies tratadas aqui é endêmica. Uma combinação nova é feita para Meniscium chrysodioides Fée var. goyazense.

Identification key for lycophytes and ferns from the Picinguaba and Santa Virgínia Nuclei, Parque Estadual da Serra do Mar, Ubatuba, SP, Brazil / Chave de identificação para licófitas e samambaias dos Núcleos Picinguaba e Santa Virgínia, Parque Estadual da Serra do Mar, Ubatuba, SP, Brasil

Abstract This work contributes to the knowledge of the fern and lycophytes diversity in the Picinguaba and Santa Virginia Nuclei, Parque Estadual da Serra do Mar (PESM), Ubatuba, São Paulo, Brazil, as well as to provide subsidies to identification of the found taxa in these areas. In total, 30 collecting expeditions were conducted and the vouchers were deposited at UEC Herbarium. We have identified 135 species distributed in 53 genera and 19 families for both areas. The most representative families were Polypodiaceae (28 species) and Dryopteridaceae (19 species), whereas Asplenium (12 species), Blechnum and Elaphoglossum (8 species each) were the most important genera. Epiphytic species predominated (62 overall), probably due to the presence of favorable habitats. Among the taxa, 41 are considered endemic from Brazil, 35 of them endemic to the Brazilian Atlantic Forest. Five species are classified as vulnerable according to the "Official list of endangered species in the State of São Paulo": Elaphoglossum macahense (Fée) Rosenst., Anetium citrifolium (L.) Splitg., Asplenium muellerianum Rosenst., Cyathea glaziovii (Fée) Domin, and Thelypteris angustifolia (Willd.) Proctor, which emphasizes the importance of preservation areas such as the Parque Estadual da Serra do Mar. An identification key has been elaborated to help with the recognition of these groups in Picinguaba and Santa Virgínia Nuclei.

Resumo Este trabalho visa contribuir para o conhecimento da diversidade de licófitas e samambaias ocorrentes nos núcleos Picinguaba e Santa Virgínia do Parque Estadual da Serra do Mar (PESM), Ubatuba, SP, Brasil, bem como fornecer subsídios para a identificação dos táxons encontrados nestas áreas. Ao todo, foram realizadas 30 expedições de coleta e o material botânico encontra-se depositado no Herbário UEC. Foram identificadas 135 espécies, 19 famílias e 53 gêneros para as duas áreas. As famílias mais representativas foram Polypodiaceae (28 espécies) e Dryopteridaceae (19 espécies), enquanto Asplenium (12 espécies), Blechnum e Elaphoglossum (8 espécies cada) foram os gêneros melhor representados. As espécies epífitas predominaram (62 ao todo), provavelmente devido à presença de hábitats favoráveis. Dos táxons encontrados, 41 são considerados endêmicos do Brasil, sendo 35 deles endêmicos da Mata Atlântica brasileira; cinco espécies são classificadas como vulneráveis, conforme a "Lista oficial de espécies ameaçadas de extinção no Estado de São Paulo": Elaphoglossum macahense (Fée) Rosenst., Anetium citrifolium (L.) Splitg., Asplenium muellerianum Rosenst., Cyathea glaziovii (Fée) Domin e Thelypteris angustifolia (Willd.) Proctor, o que ressalta a importância de áreas de preservação como o Parque Estadual da Serra do Mar, no contexto conservacionista. Uma chave de identificação foi elaborada para contribuir no reconhecimento destes grupos nos núcleos Picinguaba e Santa Virgínia.

A global plastid phylogeny of the brake fern genus Pteris (Pteridaceae) and related genera in the Pteridoideae.

The brake fern genus Pteris belongs to the Pteridaceae subfamily Pteridoideae. It contains 200-250 species distributed on all continents except Antarctica, with its highest species diversity in tropical and subtropical regions. The monophyly of Pteris has long been in question because of its great morphological diversity and because of the controversial relationships of the Australian endemic monospecific genus Platyzoma. The circumscription of the Pteridoideae has likewise been uncertain. Previous studies typically had sparse sampling of Pteris species and related genera and used limited DNA sequence data. In the present study, DNA sequences of six plastid loci of 146 accessions representing 119 species of Pteris (including the type of the genus) and 18 related genera were used to infer a phylogeny using maximum-likelihood, Bayesian-inference and maximum-parsimony methods. Our major results include: (i) the previous uncertain relationships of Platyzoma were due to long-branch attraction; (ii) Afropteris, Neurocallis, Ochropteris and Platyzoma are all embedded within a well-supported Pteris sensu lato; (iii) the traditionally circumscribed Jamesonia is paraphyletic in relation to a monophyletic Eriosorus; (iv) Pteridoideae contains 15 genera: Actiniopteris, Anogramma, Austrogramme, Cerosora, Cosentinia, Eriosorus, Jamesonia, Nephopteris (no molecular data), Onychium, Pityrogramma, Pteris, Pterozonium, Syngramma, Taenitis and Tryonia; and (v) 15 well-supported clades within Pteris are identified, which differ from one another on molecular, morphological and geographical grounds, and represent 15 major evolutionary lineages.

Global phylogeny and biogeography of grammitid ferns (Polypodiaceae).

We examined the global historical biogeography of grammitid ferns (Polypodiaceae) within a phylogenetic context. We inferred phylogenetic relationships of 190 species representing 31 of the 33 currently recognized genera of grammitid ferns by analyzing DNA sequence variation of five plastid DNA regions. We estimated the ages of cladogenetic events on an inferred phylogeny using secondary fossil calibration points. Historical biogeographical patterns were inferred via ancestral area reconstruction. Our results supported four large-scale phylogenetic and biogeographic patterns: (1) a monophyletic grammitid clade that arose among Neotropical polypod ancestors about 31.4 Ma; (2) a paraphyletic assemblage of clades distributed in the Neotropics and the Afro-Malagasy region; (3) a large clade distributed throughout the Asia-Malesia-Pacific region that originated about 23.4 Ma; and, (4) an Australian or New Zealand origin of the circumaustral genus Notogrammitis. Most genera were supported as monophyletic except for Grammitis, Oreogrammitis, Radiogrammitis, and Zygophlebia. Grammitid ferns are a well-supported monophyletic group with two biogeographically distinct lineages: a primarily Neotropical grade exhibiting several independent successful colonizations to the Afro-Malagasy region and a primarily Paleotropical clade exhibiting multiple independent dispersals to remote Pacific islands and temperate, austral regions.

Tryonia, a new taenitidoid fern genus segregated from Jamesonia and Eriosorus (Pteridaceae).

The Neotropical fern genera Eriosorus and Jamesonia have long been thought of as close relatives. Molecular phylogenetic studies have confirmed this notion but have also revealed that neither genus is monophyletic with respect to the other. As a result, all known species of Eriosorus were recently subsumed under the older generic name Jamesonia. Here, through an analysis of a four-gene plastid dataset, we show that several species traditionally treated in Eriosorus are in fact more closely related to other taenitidoid fern genera (namely Austrogramme, Pterozonium, Syngramma, and Taenitis) than they are to the large Jamesonia sensu lato clade. Tryonia Schuettp., J.Prado & A.T.Cochran gen. nov. is described to accommodate these species and four new combinations are provided. Tryonia is confined to southeastern Brazil and adjacent Uruguay; it is distinct (from most species of Jamesonia) in having stramineous rachises.

Rhagadolobiopsis, a new genus of Parmulariaceae from Brazil with a description of the ontogeny of its ascomata.

During a survey of the mycobiota of selected Brazilian ferns we discovered a new genus of Parmulariaceae causing tar spot-like symptoms on leaves of Thelypteris serrata (Thelypteridaceae). The new genus and species, decribed as Rhagadolobiopsis thelypteridis, differs from morphologically similar species of Rhagadolobium in possessing colorless, aseptate ascospores and a hymenial gel that does not become blue with iodine. In addition this is the first record of a fungus on T. serrata, and the first Parmulariaceae recorded on a member of the Thelypteridaceae. The ontogeny of the ascomata is described and illustrated here for the first time for the Parmulariaceae.

Checklist das licófitas e samambaias do Estado de São Paulo, Brasil / Checklist of lycophytes and ferns of São Paulo State, Brazil

O presente checklist usou como base a lista de licófitas e samambaias do estado de São Paulo, extraída do Catálogo de Plantas e Fungos do Brasil publicado em 2010, pelo Jardim Botânico do Rio de Janeiro (JBRJ). Aqui é apresentada uma atualização desta lista e algumas novidades melhoraram a lista básica. O número total de táxons para o estado, incluindo ambos os grupos de plantas, aumentou de 561 para 573. Dois novos registros de ocorrência foram recentemente registrados para o estado e foram incorporados no presente checklist (Pellaea flavescens Fée e P. ovata (Desv.) Weath.). Esses dados sugerem que mais estudos são necessários para o conhecimento da diversidade no estado.

The present checklist used as base the list of lycophytes and ferns of São Paulo State, extracted from the Catálogo de Plantas e Fungos do Brasil published in 2010, by the Jardim Botânico do Rio de Janeiro (JBRJ). An update of this list is here presented and some novelties improved the base list. The current total number of taxa for the state, including both plant groups, increased from 561 to 573. Two new records were recently reported to the state and were also added to the present checklist (Pellaea flavescens Fée and P. ovata (Desv.) Weath.). These data suggest that more studies are necessary to know the diversity in the state.

Cell wall polysaccharides from fern leaves: evidence for a mannan-rich Type III cell wall in Adiantum raddianum.

Primary cell walls from plants are composites of cellulose tethered by cross-linking glycans and embedded in a matrix of pectins. Cell wall composition varies between plant species, reflecting in some instances the evolutionary distance between them. In this work the monosaccharide compositions of isolated primary cell walls of nine fern species and one lycophyte were characterized and compared with those from Equisetum and an angiosperm dicot. The relatively high abundance of mannose in these plants suggests that mannans may constitute the major cross-linking glycan in the primary walls of pteridophytes and lycophytes. Pectin-related polysaccharides contained mostly rhamnose and uronic acids, indicating the presence of rhamnogalacturonan I highly substituted with galactose and arabinose. Structural and fine-structural analyses of the hemicellulose fraction of leaves of Adiantum raddianum confirmed this hypothesis. Linkage analysis showed that the mannan contains mostly 4-Man with very little 4,6-Man, indicating a low percentage of branching with galactose. Treatment of the mannan-rich fractions with endo-ß-mannanase produced characteristic mannan oligosaccharides. Minor amounts of xyloglucan and xylans were also detected. These data and those of others suggest that all vascular plants contain xyloglucans, arabinoxylans, and (gluco)mannans, but in different proportions that define cell wall types. Whereas xyloglucan and pectin-rich walls define Type I walls of dicots and many monocots, arabinoxylans and lower proportion of pectin define the Type II walls of commelinoid monocots. The mannan-rich primary walls with low pectins of many ferns and a lycopod indicate a fundamentally different wall type among land plants, the Type III wall.

A composição florística e a diversidade de pteridófitas diferem entre a Floresta de Restinga e a Floresta Ombrófila Densa das Terras Baixas do Núcleo Picinguaba/PESM, Ubatuba/SP? / Ferns composition and diversity differ between Restinga and Lowland Rainforest areas in the Serra do Mar?

As pteridófitas constituem um componente importante da flora tropical, representando aproximadamente 10 por cento do total de plantas vasculares de florestas tropicais, sendo o grupo dominante entre a vegetação herbácea. O objetivo do trabalho foi verificar se as comunidades de pteridófitas de duas áreas de Mata Atlântica, Floresta de Restinga (FRS) e Floresta Ombrófila Densa de Terras Baixas (FTB), situadas sobre solos notavelmente distintos e separadas por uma grande rodovia, difeririam em sua composição florística e diversidade. Estas duas fisionomias estão localizadas no Núcleo Picinguaba do Parque Estadual da Serra do Mar, Ubatuba, São Paulo (23° 31' a 23° 34' S e 45° 02' a 45° 05' W). Em cada área delimitamos sete parcelas de 20 × 20 m, nas quais os indivíduos foram coletados, identificados e recenseados. Efetuamos três métodos de análise multivariada (TWINSPAN, UPGMA e PCO) para verificar a existência de grupos florísticos; calculamos o índice de Payandeh para definirmos o nível de agregação de cada espécie em cada uma das duas áreas (FRS e FTB); obtivemos espécies indicadoras para cada área; e realizamos análises de diversidade (riqueza, equabilidade e heterogeneidade). Nas duas áreas amostramos 3.482 indivíduos, dos quais 1.366 ocorrem na FRS e 2.116 na FTB. Encontramos 14 espécies na FRS e 29 na FTB; cinco espécies foram compartilhadas entre as duas áreas. As análises de grupos florísticos mostraram a formação de dois blocos bem definidos (FRS × FTB). Na FRS, relativamente mais espécies apresentaram distribuição agregada e menos espécies apresentaram distribuição aleatória em relação à FTB. Encontramos quatro espécies indicadoras para a FRS e oito para a FTB. As curvas resultantes da rarefação por indivíduos indicaram forte diferença de riqueza específica entre as duas comunidades, favorável à FTB. As diferenças encontradas podem estar relacionadas às características físico-químicas do solo (mais fértil e menos tóxico na FTB), à dinâmica da água (as espécies vegetais da FRS estão, de modo geral, sujeitas ao estresse hídrico) e ao impacto causado pela estrada que corta o Parque. Esses aspectos poderiam estar relacionados a diferentes formas de ocupação de nichos e ao fato de que algumas espécies em ambientes com recursos limitados e distribuídos heterogeneamente no espaço, como é o caso da Restinga estudada, eliminariam as demais.

Ferns are an important component of the tropical flora, representing about 10 percent of all vascular plants of tropical forests, constituting the dominant group among the herbaceous vegetation. The aim of this study was to determine whether the ferns communities in two areas of Atlantic Forest, Restinga (FRS) and Lowland Ombrophilous Dense (FTB) forests, located on soils remarkably distinct and separated by a highway, differ in their floristic composition and diversity. These two faces are located in Picinguaba locality, Parque Estadual da Serra do Mar, Ubatuba, São Paulo (23° 31' to 23° 34' S and 45° 02' to 45° 05' W). We delimited seven plots of 20 × 20 m in each area, collected, identified and listed the fern individuals. We performed three methods of multivariate analysis (TWINSPAN, UPGMA and PCO) to verify the existence of floristic groups; calculated the Payandeh index to define the level of aggregation of each species in each of the two areas (FRS and FTB); obtained indicator species for each area; and performed diversity analysis (richness, evenness and heterogeneity). The two areas sampled 3482 individuals, 1366 of which occur in FRS and 2116 in FTB. We found 14 species in FRS and 29 in FTB; these areas shared five species. We found two well-defined floristic blocks (FRS × FTB) in cluster analysis. In the FRS, relatively most species showed aggregated distribution and fewer species showed random distribution in relation to FTB. We found four indicator species for FRS and eight for FTB. The curves resulting from the individual-based rarefaction indicated a strong difference in species richness between the two communities, in favor to FTB. These differences may be related to physical and chemical characteristics of soil (more fertile and less toxic in the FTB), water dynamics (plant species in the FRS are generally subject to water stress) and the sharp break caused by highway that cuts through the park. These aspects could be related to different forms of occupation of niches and to the fact that some species in environments with limited resources and heterogeneously distributed in space, such as the studied Restinga, would eliminate the others.